/*
 * vk_mvk_moltenvk.h
 *
 * Copyright (c) 2014-2018 The Brenwill Workshop Ltd. (http://www.brenwill.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


/** Vulkan extension VK_MVK_moltenvk. */

#ifndef __vk_mvk_moltenvk_h_
#define __vk_mvk_moltenvk_h_ 1

#ifdef __cplusplus
extern "C" {
#endif	//  __cplusplus
	
#include <vulkan/vulkan.h>

#ifdef __OBJC__
#import <Metal/Metal.h>
#import <IOSurface/IOSurfaceRef.h>
#endif


/**
 * The version number of MoltenVK is a single integer value, derived from the Major, Minor,
 * and Patch version values, where each of the Major, Minor, and Patch components is allocated
 * two decimal digits, in the format MjMnPt. This creates a version number that is both human
 * readable and allows efficient computational comparisons to a single integer number.
 *
 * The following examples illustrate how the MoltenVK version number is built from its components:
 *   - 002000    (version 0.20.0)
 *   - 010000    (version 1.0.0)
 *   - 030104    (version 3.1.4)
 *   - 401215    (version 4.12.15)
 */
#define MVK_VERSION_MAJOR   1
#define MVK_VERSION_MINOR   0
#define MVK_VERSION_PATCH   5

#define MVK_MAKE_VERSION(major, minor, patch)    (((major) * 10000) + ((minor) * 100) + (patch))
#define MVK_VERSION     MVK_MAKE_VERSION(MVK_VERSION_MAJOR, MVK_VERSION_MINOR, MVK_VERSION_PATCH)


#define VK_MVK_MOLTENVK_SPEC_VERSION            4
#define VK_MVK_MOLTENVK_EXTENSION_NAME			"VK_MVK_moltenvk"

/** MoltenVK configuration settings. */
typedef struct {
    VkBool32 debugMode;                     /**< If enabled, several debugging capabilities will be enabled. Shader code will be logged during Runtime Shader Conversion. Adjusts settings that might trigger Metal validation but are otherwise acceptable to Metal runtime. Improves support for Xcode GPU Frame Capture. Default value is determined at build time by the presence of a DEBUG build setting. By default the DEBUG build setting is defined when MoltenVK is compiled in Debug mode, and not defined when compiled in Release mode. */
    VkBool32 shaderConversionFlipVertexY;   /**< If enabled, MSL vertex shader code created during Runtime Shader Conversion will flip the Y-axis of each vertex, as Vulkan coordinate system is inverse of OpenGL. Default is true. */
    VkBool32 supportLargeQueryPools;        /**< Metal allows only 8192 occlusion queries per MTLBuffer. If enabled, MoltenVK allocates a MTLBuffer for each query pool, allowing each query pool to support 8192 queries, which may slow performance or cause unexpected behaviour if the query pool is not established prior to a Metal renderpass, or if the query pool is changed within a Metal renderpass. If disabled, one MTLBuffer will be shared by all query pools, which improves performance, but limits the total device queries to 8192. Default is false. */
	VkBool32 presentWithCommandBuffer;      /**< If enabled, each surface presentation is scheduled using a command buffer. Enabling this may improve rendering frame synchronization, but may result in reduced frame rates. Default value is false if the MVK_PRESENT_WITHOUT_COMMAND_BUFFER build setting is defined when MoltenVK is compiled, and true otherwise. By default the MVK_PRESENT_WITHOUT_COMMAND_BUFFER build setting is not defined and the value of this setting is true. */
    VkBool32 displayWatermark;              /**< If enabled, a MoltenVK logo watermark will be rendered on top of the scene. This can be enabled for publicity during demos. Default value is true if the MVK_DISPLAY_WATERMARK build setting is defined when MoltenVK is compiled, and false otherwise. By default the MVK_DISPLAY_WATERMARK build setting is not defined. */
    VkBool32 performanceTracking;           /**< If enabled, per-frame performance statistics are tracked, optionally logged, and can be retrieved via the vkGetSwapchainPerformanceMVK() function, and various shader compilation performance statistics are tracked, logged, and can be retrieved via the vkGetShaderCompilationPerformanceMVK() function. Default is false. */
    uint32_t performanceLoggingFrameCount;  /**< If non-zero, performance statistics will be periodically logged to the console, on a repeating cycle of this many frames per swapchain. The performanceTracking capability must also be enabled. Default is zero, indicating no logging. */
} MVKDeviceConfiguration;

/** Features provided by the current implementation of Metal on the current device. */
typedef struct {
    uint32_t mslVersion;                        /**< The version of the Metal Shading Language available on this device. The format of the integer is MMmmpp, with two decimal digts each for Major, minor, and patch version values (eg. MSL 1.2 would appear as 010200). */
	VkBool32 indirectDrawing;                   /**< If true, draw calls support parameters held in a GPU buffer. */
	VkBool32 baseVertexInstanceDrawing;         /**< If true, draw calls support specifiying the base vertex and instance. */
    VkBool32 dynamicMTLBuffers;                 /**< If true, dynamic MTLBuffers for setting vertex, fragment, and compute bytes are supported. */
    VkBool32 shaderSpecialization;              /**< If true, shader specialization (aka Metal function constants) is supported. */
    VkBool32 ioSurfaces;                        /**< If true, VkImages can be underlaid by IOSurfaces via the vkUseIOSurfaceMVK() function, to support inter-process image transfers. */
    VkBool32 texelBuffers;                      /**< If true, texel buffers are supported, allowing the contents of a buffer to be interpreted as an image via a VkBufferView. */
    VkBool32 depthClipMode;                     /**< If true, the device supports both depth clipping and depth clamping per the depthClampEnable flag of VkPipelineRasterizationStateCreateInfo in VkGraphicsPipelineCreateInfo. */
	VkBool32 presentModeImmediate;              /**< If true, the device supports immediate surface present mode (VK_PRESENT_MODE_IMMEDIATE_KHR), allowing a swapchain image to be presented immediately, without waiting for the vertical sync period of the display. */
	uint32_t maxPerStageBufferCount;            /**< The total number of per-stage Metal buffers available for shader uniform content and attributes. */
    uint32_t maxPerStageTextureCount;           /**< The total number of per-stage Metal textures available for shader uniform content. */
    uint32_t maxPerStageSamplerCount;           /**< The total number of per-stage Metal samplers available for shader uniform content. */
    VkDeviceSize maxMTLBufferSize;              /**< The max size of a MTLBuffer (in bytes). */
    VkDeviceSize mtlBufferAlignment;            /**< The alignment used when allocating memory for MTLBuffers. Must be PoT. */
    VkDeviceSize maxQueryBufferSize;            /**< The maximum size of an occlusion query buffer (in bytes). */
	VkDeviceSize mtlCopyBufferAlignment;        /**< The alignment required during buffer copy operations (in bytes). */
    VkSampleCountFlags supportedSampleCounts;   /**< A bitmask identifying the sample counts supported by the device. */
} MVKPhysicalDeviceMetalFeatures;

/** MoltenVK swapchain performance statistics. */
typedef struct {
    double lastFrameInterval;           /**< The time interval between this frame and the immediately previous frame, in milliseconds. */
    double averageFrameInterval;        /**< The rolling average time interval between frames, in miliseconds. This value has less volatility than the lastFrameInterval value. */
    double averageFramesPerSecond;      /**< The rolling average number of frames per second. This is simply the 1000 divided by the averageFrameInterval value. */
} MVKSwapchainPerformance;

/** MoltenVK performance of a particular type of shader compilation event. */
typedef struct {
    uint32_t count;             /**< The number of compilation events of this type. */
    double averageDuration;     /**< The average duration of the compilation event, in milliseconds. */
    double minimumDuration;     /**< The minimum duration of the compilation event, in milliseconds. */
    double maximumDuration;     /**< The maximum duration of the compilation event, in milliseconds. */
} MVKShaderCompilationEventPerformance;

/** MoltenVK performance of shader compilation events for a VkDevice. */
typedef struct {
	MVKShaderCompilationEventPerformance hashShaderCode;            /** Create a hash from the incoming shader code. */
    MVKShaderCompilationEventPerformance spirvToMSL;                /** Convert SPIR-V to MSL source code. */
    MVKShaderCompilationEventPerformance mslCompile;                /** Compile MSL source code into a MTLLibrary. */
    MVKShaderCompilationEventPerformance mslLoad;                   /** Load pre-compiled MSL code into a MTLLibrary. */
	MVKShaderCompilationEventPerformance shaderLibraryFromCache;    /** Retrieve a shader library from the cache, lazily creating it if needed. */
    MVKShaderCompilationEventPerformance functionRetrieval;         /** Retrieve a MTLFunction from a MTLLibrary. */
    MVKShaderCompilationEventPerformance functionSpecialization;    /** Specialize a retrieved MTLFunction. */
    MVKShaderCompilationEventPerformance pipelineCompile;           /** Compile MTLFunctions into a pipeline. */
	MVKShaderCompilationEventPerformance sizePipelineCache;         /** Calculate the size of cache data required to write MSL to pipeline cache data stream. */
	MVKShaderCompilationEventPerformance writePipelineCache;        /** Write MSL to pipeline cache data stream. */
	MVKShaderCompilationEventPerformance readPipelineCache;         /** Read MSL from pipeline cache data stream. */
} MVKShaderCompilationPerformance;


#pragma mark -
#pragma mark Function types

typedef void (VKAPI_PTR *PFN_vkGetMoltenVKDeviceConfigurationMVK)(VkDevice device, MVKDeviceConfiguration* pConfiguration);
typedef VkResult (VKAPI_PTR *PFN_vkSetMoltenVKDeviceConfigurationMVK)(VkDevice device, MVKDeviceConfiguration* pConfiguration);
typedef void (VKAPI_PTR *PFN_vkGetPhysicalDeviceMetalFeaturesMVK)(VkPhysicalDevice physicalDevice, MVKPhysicalDeviceMetalFeatures* pMetalFeatures);
typedef void (VKAPI_PTR *PFN_vkGetSwapchainPerformanceMVK)(VkDevice device, VkSwapchainKHR swapchain, MVKSwapchainPerformance* pSwapchainPerf);
typedef void (VKAPI_PTR *PFN_vkGetShaderCompilationPerformanceMVK)(VkDevice device, MVKShaderCompilationPerformance* pShaderCompPerf);
typedef void (VKAPI_PTR *PFN_vkGetVersionStringsMVK)(char* pMoltenVersionStringBuffer, uint32_t moltenVersionStringBufferLength, char* pVulkanVersionStringBuffer, uint32_t vulkanVersionStringBufferLength);

#ifdef __OBJC__
typedef void (VKAPI_PTR *PFN_vkGetMTLDeviceMVK)(VkPhysicalDevice physicalDevice, id<MTLDevice>* pMTLDevice);
typedef VkResult (VKAPI_PTR *PFN_vkSetMTLTextureMVK)(VkImage image, id<MTLTexture> mtlTexture);
typedef void (VKAPI_PTR *PFN_vkGetMTLTextureMVK)(VkImage image, id<MTLTexture>* pMTLTexture);
typedef VkResult (VKAPI_PTR *PFN_vkUseIOSurfaceMVK)(VkImage image, IOSurfaceRef ioSurface);
typedef void (VKAPI_PTR *PFN_vkGetIOSurfaceMVK)(VkImage image, IOSurfaceRef* pIOSurface);
#endif // __OBJC__

#pragma mark Deprecated license functions
typedef VkResult (VKAPI_PTR *PFN_vkActivateMoltenVKLicenseMVK)(const char* licenseID, const char* licenseKey, VkBool32 acceptLicenseTermsAndConditions);
typedef VkResult (VKAPI_PTR *PFN_vkActivateMoltenVKLicensesMVK)();


#pragma mark -
#pragma mark Function prototypes

#ifndef VK_NO_PROTOTYPES

/** 
 * Populates the pConfiguration structure with the current MoltenVK configuration settings 
 * of the specified device. 
 *
 * To change a specific configuration value, call vkGetMoltenVKDeviceConfigurationMVK()
 * to retrieve the current configuration, make changes, and call 
 * vkSetMoltenVKDeviceConfigurationMVK() to update all of the values.
 */
VKAPI_ATTR void VKAPI_CALL vkGetMoltenVKDeviceConfigurationMVK(
    VkDevice                                    device,
    MVKDeviceConfiguration*                     pConfiguration);

/** 
 * Sets the MoltenVK configuration settings of the specified device to those found in the 
 * pConfiguration structure.
 *
 * To change a specific configuration value, call vkGetMoltenVKDeviceConfigurationMVK()
 * to retrieve the current configuration, make changes, and call
 * vkSetMoltenVKDeviceConfigurationMVK() to update all of the values.
 */
VKAPI_ATTR VkResult VKAPI_CALL vkSetMoltenVKDeviceConfigurationMVK(
    VkDevice                                    device,
    MVKDeviceConfiguration*                     pConfiguration);

/** 
 * Populates the pMetalFeatures structure with the Metal-specific features
 * supported by the specified physical device. 
 */
VKAPI_ATTR void VKAPI_CALL vkGetPhysicalDeviceMetalFeaturesMVK(
	VkPhysicalDevice                            physicalDevice,
	MVKPhysicalDeviceMetalFeatures*             pMetalFeatures);

/**
 * Populates the specified MVKSwapchainPerformance structure with
 * the current performance statistics for the specified swapchain.
 */
VKAPI_ATTR void VKAPI_CALL vkGetSwapchainPerformanceMVK(
    VkDevice                                    device,
    VkSwapchainKHR                              swapchain,
    MVKSwapchainPerformance*                    pSwapchainPerf);

/**
 * Populates the specified MVKShaderCompilationPerformance structure with the
 * current shader compilation performance statistics for the specified device.
 */
VKAPI_ATTR void VKAPI_CALL vkGetShaderCompilationPerformanceMVK(
    VkDevice                                    device,
    MVKShaderCompilationPerformance*            pShaderCompPerf);

/**
 * Returns a human readable version of the MoltenVK and Vulkan versions.
 *
 * This function is provided as a convenience for reporting. Use the MVK_VERSION, 
 * VK_API_VERSION_1_0, and VK_HEADER_VERSION macros for programmatically accessing
 * the corresponding version numbers.
 */
VKAPI_ATTR void VKAPI_CALL vkGetVersionStringsMVK(
    char*                                       pMoltenVersionStringBuffer,
    uint32_t                                    moltenVersionStringBufferLength,
    char*                                       pVulkanVersionStringBuffer,
    uint32_t                                    vulkanVersionStringBufferLength);


#ifdef __OBJC__

/** Returns, in the pMTLDevice pointer, the MTLDevice used by the VkPhysicalDevice. */
VKAPI_ATTR void VKAPI_CALL vkGetMTLDeviceMVK(
    VkPhysicalDevice                           physicalDevice,
    id<MTLDevice>*                             pMTLDevice);

/**
 * Sets the VkImage to use the specified MTLTexture.
 *
 * Any differences in the properties of mtlTexture and this image will modify the
 * properties of this image.
 *
 * If a MTLTexture has already been created for this image, it will be destroyed.
 *
 * Returns VK_SUCCESS.
 */
VKAPI_ATTR VkResult VKAPI_CALL vkSetMTLTextureMVK(
    VkImage                                     image,
    id<MTLTexture>                              mtlTexture);

/** Returns, in the pMTLTexture pointer, the MTLTexture currently underlaying the VkImage. */
VKAPI_ATTR void VKAPI_CALL vkGetMTLTextureMVK(
    VkImage                                     image,
    id<MTLTexture>*                             pMTLTexture);

/**
 * Indicates that a VkImage should use an IOSurface to underlay the Metal texture.
 *
 * If ioSurface is not null, it will be used as the IOSurface, and any differences
 * in the properties of that IOSurface will modify the properties of this image.
 *
 * If ioSurface is null, this image will create and use an IOSurface
 * whose properties are compatible with the properties of this image.
 *
 * If a MTLTexture has already been created for this image, it will be destroyed.
 *
 * Returns:
 *   - VK_SUCCESS.
 *   - VK_ERROR_FEATURE_NOT_PRESENT if IOSurfaces are not supported on the platform.
 *   - VK_ERROR_INITIALIZATION_FAILED if ioSurface is specified and is not compatible with this VkImage.
 */
VKAPI_ATTR VkResult VKAPI_CALL vkUseIOSurfaceMVK(
    VkImage                                     image,
    IOSurfaceRef                                ioSurface);


/**
 * Returns, in the pIOSurface pointer, the IOSurface currently underlaying the VkImage,
 * as set by the useIOSurfaceMVK() function, or returns null if the VkImage is not using
 * an IOSurface, or if the platform does not support IOSurfaces.
 */
VKAPI_ATTR void VKAPI_CALL vkGetIOSurfaceMVK(
    VkImage                                     image,
    IOSurfaceRef*                               pIOSurface);


#endif // __OBJC__


#pragma mark -
#pragma mark Shaders

/**
 * Enumerates the magic number values to set in the MVKMSLSPIRVHeader when
 * submitting a SPIR-V stream that contains either Metal Shading Language source
 * code or Metal Shading Language compiled binary code in place of SPIR-V code.
 */
typedef enum {
    kMVKMagicNumberSPIRVCode        = 0x07230203,    /**< SPIR-V stream contains standard SPIR-V code. */
    kMVKMagicNumberMSLSourceCode    = 0x19960412,    /**< SPIR-V stream contains Metal Shading Language source code. */
    kMVKMagicNumberMSLCompiledCode  = 0x19981215,    /**< SPIR-V stream contains Metal Shading Language compiled binary code. */
} MVKMSLMagicNumber;

/**
 * Describes the header at the start of an SPIR-V stream, when it contains either
 * Metal Shading Language source code or Metal Shading Language compiled binary code.
 *
 * To submit MSL source code to the vkCreateShaderModule() function in place of SPIR-V
 * code, prepend a MVKMSLSPIRVHeader containing the kMVKMagicNumberMSLSourceCode magic
 * number to the MSL source code. The MSL source code must be null-terminated.
 *
 * To submit MSL compiled binary code to the vkCreateShaderModule() function in place of
 * SPIR-V code, prepend a MVKMSLSPIRVHeader containing the kMVKMagicNumberMSLCompiledCode
 * magic number to the MSL compiled binary code.
 *
 * In both cases, the pCode element of VkShaderModuleCreateInfo should pointer to the
 * location of the MVKMSLSPIRVHeader, and the MSL code should start at the byte immediately
 * after the MVKMSLSPIRVHeader.
 *
 * The codeSize element of VkShaderModuleCreateInfo should be set to the entire size of
 * the submitted code memory, including the additional sizeof(MVKMSLSPIRVHeader) bytes
 * taken up by the MVKMSLSPIRVHeader, and, in the case of MSL source code, including
 * the null-terminator byte.
 */
typedef uint32_t MVKMSLSPIRVHeader;


#pragma mark Deprecated license functions
__attribute__((deprecated("MoltenVK no longer requires a runtime license.")))
VKAPI_ATTR VkResult VKAPI_CALL vkActivateMoltenVKLicenseMVK(const char* licenseID, const char* licenseKey, VkBool32 acceptLicenseTermsAndConditions);
__attribute__((deprecated("MoltenVK no longer requires a runtime license.")))
VKAPI_ATTR static inline void VKAPI_CALL vkActivateMoltenVKLicensesMVK()  {}

#endif // VK_NO_PROTOTYPES


#ifdef __cplusplus
}
#endif	//  __cplusplus

#endif